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Diffstat (limited to 'apps/codecs/libwmapro/get_bits.h')
| -rw-r--r-- | apps/codecs/libwmapro/get_bits.h | 691 |
1 files changed, 691 insertions, 0 deletions
diff --git a/apps/codecs/libwmapro/get_bits.h b/apps/codecs/libwmapro/get_bits.h new file mode 100644 index 0000000000..c325778d67 --- /dev/null +++ b/apps/codecs/libwmapro/get_bits.h @@ -0,0 +1,691 @@ +/* + * copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at> + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/** + * @file libavcodec/get_bits.h + * bitstream reader API header. + */ + +#ifndef AVCODEC_GET_BITS_H +#define AVCODEC_GET_BITS_H + +#include <stdint.h> +#include <stdlib.h> +#include <assert.h> +#include "libavutil/bswap.h" +#include "libavutil/common.h" +#include "libavutil/intreadwrite.h" +#include "libavutil/log.h" +#include "mathops.h" + +#if defined(ALT_BITSTREAM_READER_LE) && !defined(ALT_BITSTREAM_READER) +# define ALT_BITSTREAM_READER +#endif + +#if !defined(LIBMPEG2_BITSTREAM_READER) && !defined(A32_BITSTREAM_READER) && !defined(ALT_BITSTREAM_READER) +# if ARCH_ARM && !HAVE_FAST_UNALIGNED +# define A32_BITSTREAM_READER +# else +# define ALT_BITSTREAM_READER +//#define LIBMPEG2_BITSTREAM_READER +//#define A32_BITSTREAM_READER +# endif +#endif + +/* bit input */ +/* buffer, buffer_end and size_in_bits must be present and used by every reader */ +typedef struct GetBitContext { + const uint8_t *buffer, *buffer_end; +#ifdef ALT_BITSTREAM_READER + int index; +#elif defined LIBMPEG2_BITSTREAM_READER + uint8_t *buffer_ptr; + uint32_t cache; + int bit_count; +#elif defined A32_BITSTREAM_READER + uint32_t *buffer_ptr; + uint32_t cache0; + uint32_t cache1; + int bit_count; +#endif + int size_in_bits; +} GetBitContext; + +#define VLC_TYPE int16_t + +typedef struct VLC { + int bits; + VLC_TYPE (*table)[2]; ///< code, bits + int table_size, table_allocated; +} VLC; + +typedef struct RL_VLC_ELEM { + int16_t level; + int8_t len; + uint8_t run; +} RL_VLC_ELEM; + +/* Bitstream reader API docs: +name + arbitrary name which is used as prefix for the internal variables + +gb + getbitcontext + +OPEN_READER(name, gb) + loads gb into local variables + +CLOSE_READER(name, gb) + stores local vars in gb + +UPDATE_CACHE(name, gb) + refills the internal cache from the bitstream + after this call at least MIN_CACHE_BITS will be available, + +GET_CACHE(name, gb) + will output the contents of the internal cache, next bit is MSB of 32 or 64 bit (FIXME 64bit) + +SHOW_UBITS(name, gb, num) + will return the next num bits + +SHOW_SBITS(name, gb, num) + will return the next num bits and do sign extension + +SKIP_BITS(name, gb, num) + will skip over the next num bits + note, this is equivalent to SKIP_CACHE; SKIP_COUNTER + +SKIP_CACHE(name, gb, num) + will remove the next num bits from the cache (note SKIP_COUNTER MUST be called before UPDATE_CACHE / CLOSE_READER) + +SKIP_COUNTER(name, gb, num) + will increment the internal bit counter (see SKIP_CACHE & SKIP_BITS) + +LAST_SKIP_CACHE(name, gb, num) + will remove the next num bits from the cache if it is needed for UPDATE_CACHE otherwise it will do nothing + +LAST_SKIP_BITS(name, gb, num) + is equivalent to LAST_SKIP_CACHE; SKIP_COUNTER + +for examples see get_bits, show_bits, skip_bits, get_vlc +*/ + +#ifdef ALT_BITSTREAM_READER +# define MIN_CACHE_BITS 25 + +# define OPEN_READER(name, gb)\ + unsigned int name##_index= (gb)->index;\ + int name##_cache= 0;\ + +# define CLOSE_READER(name, gb)\ + (gb)->index= name##_index;\ + +# ifdef ALT_BITSTREAM_READER_LE +# define UPDATE_CACHE(name, gb)\ + name##_cache= AV_RL32( ((const uint8_t *)(gb)->buffer)+(name##_index>>3) ) >> (name##_index&0x07);\ + +# define SKIP_CACHE(name, gb, num)\ + name##_cache >>= (num); +# else +# define UPDATE_CACHE(name, gb)\ + name##_cache= AV_RB32( ((const uint8_t *)(gb)->buffer)+(name##_index>>3) ) << (name##_index&0x07);\ + +# define SKIP_CACHE(name, gb, num)\ + name##_cache <<= (num); +# endif + +// FIXME name? +# define SKIP_COUNTER(name, gb, num)\ + name##_index += (num);\ + +# define SKIP_BITS(name, gb, num)\ + {\ + SKIP_CACHE(name, gb, num)\ + SKIP_COUNTER(name, gb, num)\ + }\ + +# define LAST_SKIP_BITS(name, gb, num) SKIP_COUNTER(name, gb, num) +# define LAST_SKIP_CACHE(name, gb, num) ; + +# ifdef ALT_BITSTREAM_READER_LE +# define SHOW_UBITS(name, gb, num)\ + zero_extend(name##_cache, num) + +# define SHOW_SBITS(name, gb, num)\ + sign_extend(name##_cache, num) +# else +# define SHOW_UBITS(name, gb, num)\ + NEG_USR32(name##_cache, num) + +# define SHOW_SBITS(name, gb, num)\ + NEG_SSR32(name##_cache, num) +# endif + +# define GET_CACHE(name, gb)\ + ((uint32_t)name##_cache) + +static inline int get_bits_count(const GetBitContext *s){ + return s->index; +} + +static inline void skip_bits_long(GetBitContext *s, int n){ + s->index += n; +} + +#elif defined LIBMPEG2_BITSTREAM_READER +//libmpeg2 like reader + +# define MIN_CACHE_BITS 17 + +# define OPEN_READER(name, gb)\ + int name##_bit_count=(gb)->bit_count;\ + int name##_cache= (gb)->cache;\ + uint8_t * name##_buffer_ptr=(gb)->buffer_ptr;\ + +# define CLOSE_READER(name, gb)\ + (gb)->bit_count= name##_bit_count;\ + (gb)->cache= name##_cache;\ + (gb)->buffer_ptr= name##_buffer_ptr;\ + +# define UPDATE_CACHE(name, gb)\ + if(name##_bit_count >= 0){\ + name##_cache+= AV_RB16(name##_buffer_ptr) << name##_bit_count; \ + name##_buffer_ptr+=2;\ + name##_bit_count-= 16;\ + }\ + +# define SKIP_CACHE(name, gb, num)\ + name##_cache <<= (num);\ + +# define SKIP_COUNTER(name, gb, num)\ + name##_bit_count += (num);\ + +# define SKIP_BITS(name, gb, num)\ + {\ + SKIP_CACHE(name, gb, num)\ + SKIP_COUNTER(name, gb, num)\ + }\ + +# define LAST_SKIP_BITS(name, gb, num) SKIP_BITS(name, gb, num) +# define LAST_SKIP_CACHE(name, gb, num) SKIP_CACHE(name, gb, num) + +# define SHOW_UBITS(name, gb, num)\ + NEG_USR32(name##_cache, num) + +# define SHOW_SBITS(name, gb, num)\ + NEG_SSR32(name##_cache, num) + +# define GET_CACHE(name, gb)\ + ((uint32_t)name##_cache) + +static inline int get_bits_count(const GetBitContext *s){ + return (s->buffer_ptr - s->buffer)*8 - 16 + s->bit_count; +} + +static inline void skip_bits_long(GetBitContext *s, int n){ + OPEN_READER(re, s) + re_bit_count += n; + re_buffer_ptr += 2*(re_bit_count>>4); + re_bit_count &= 15; + re_cache = ((re_buffer_ptr[-2]<<8) + re_buffer_ptr[-1]) << (16+re_bit_count); + UPDATE_CACHE(re, s) + CLOSE_READER(re, s) +} + +#elif defined A32_BITSTREAM_READER + +# define MIN_CACHE_BITS 32 + +# define OPEN_READER(name, gb)\ + int name##_bit_count=(gb)->bit_count;\ + uint32_t name##_cache0= (gb)->cache0;\ + uint32_t name##_cache1= (gb)->cache1;\ + uint32_t * name##_buffer_ptr=(gb)->buffer_ptr;\ + +# define CLOSE_READER(name, gb)\ + (gb)->bit_count= name##_bit_count;\ + (gb)->cache0= name##_cache0;\ + (gb)->cache1= name##_cache1;\ + (gb)->buffer_ptr= name##_buffer_ptr;\ + +# define UPDATE_CACHE(name, gb)\ + if(name##_bit_count > 0){\ + const uint32_t next= be2me_32( *name##_buffer_ptr );\ + name##_cache0 |= NEG_USR32(next,name##_bit_count);\ + name##_cache1 |= next<<name##_bit_count;\ + name##_buffer_ptr++;\ + name##_bit_count-= 32;\ + }\ + +#if ARCH_X86 +# define SKIP_CACHE(name, gb, num)\ + __asm__(\ + "shldl %2, %1, %0 \n\t"\ + "shll %2, %1 \n\t"\ + : "+r" (name##_cache0), "+r" (name##_cache1)\ + : "Ic" ((uint8_t)(num))\ + ); +#else +# define SKIP_CACHE(name, gb, num)\ + name##_cache0 <<= (num);\ + name##_cache0 |= NEG_USR32(name##_cache1,num);\ + name##_cache1 <<= (num); +#endif + +# define SKIP_COUNTER(name, gb, num)\ + name##_bit_count += (num);\ + +# define SKIP_BITS(name, gb, num)\ + {\ + SKIP_CACHE(name, gb, num)\ + SKIP_COUNTER(name, gb, num)\ + }\ + +# define LAST_SKIP_BITS(name, gb, num) SKIP_BITS(name, gb, num) +# define LAST_SKIP_CACHE(name, gb, num) SKIP_CACHE(name, gb, num) + +# define SHOW_UBITS(name, gb, num)\ + NEG_USR32(name##_cache0, num) + +# define SHOW_SBITS(name, gb, num)\ + NEG_SSR32(name##_cache0, num) + +# define GET_CACHE(name, gb)\ + (name##_cache0) + +static inline int get_bits_count(const GetBitContext *s){ + return ((uint8_t*)s->buffer_ptr - s->buffer)*8 - 32 + s->bit_count; +} + +static inline void skip_bits_long(GetBitContext *s, int n){ + OPEN_READER(re, s) + re_bit_count += n; + re_buffer_ptr += re_bit_count>>5; + re_bit_count &= 31; + re_cache0 = be2me_32( re_buffer_ptr[-1] ) << re_bit_count; + re_cache1 = 0; + UPDATE_CACHE(re, s) + CLOSE_READER(re, s) +} + +#endif + +/** + * read mpeg1 dc style vlc (sign bit + mantisse with no MSB). + * if MSB not set it is negative + * @param n length in bits + * @author BERO + */ +static inline int get_xbits(GetBitContext *s, int n){ + register int sign; + register int32_t cache; + OPEN_READER(re, s) + UPDATE_CACHE(re, s) + cache = GET_CACHE(re,s); + sign=(~cache)>>31; + LAST_SKIP_BITS(re, s, n) + CLOSE_READER(re, s) + return (NEG_USR32(sign ^ cache, n) ^ sign) - sign; +} + +static inline int get_sbits(GetBitContext *s, int n){ + register int tmp; + OPEN_READER(re, s) + UPDATE_CACHE(re, s) + tmp= SHOW_SBITS(re, s, n); + LAST_SKIP_BITS(re, s, n) + CLOSE_READER(re, s) + return tmp; +} + +/** + * reads 1-17 bits. + * Note, the alt bitstream reader can read up to 25 bits, but the libmpeg2 reader can't + */ +static inline unsigned int get_bits(GetBitContext *s, int n){ + register int tmp; + OPEN_READER(re, s) + UPDATE_CACHE(re, s) + tmp= SHOW_UBITS(re, s, n); + LAST_SKIP_BITS(re, s, n) + CLOSE_READER(re, s) + return tmp; +} + +/** + * shows 1-17 bits. + * Note, the alt bitstream reader can read up to 25 bits, but the libmpeg2 reader can't + */ +static inline unsigned int show_bits(GetBitContext *s, int n){ + register int tmp; + OPEN_READER(re, s) + UPDATE_CACHE(re, s) + tmp= SHOW_UBITS(re, s, n); +// CLOSE_READER(re, s) + return tmp; +} + +static inline void skip_bits(GetBitContext *s, int n){ + //Note gcc seems to optimize this to s->index+=n for the ALT_READER :)) + OPEN_READER(re, s) + UPDATE_CACHE(re, s) + LAST_SKIP_BITS(re, s, n) + CLOSE_READER(re, s) +} + +static inline unsigned int get_bits1(GetBitContext *s){ +#ifdef ALT_BITSTREAM_READER + unsigned int index= s->index; + uint8_t result= s->buffer[ index>>3 ]; +#ifdef ALT_BITSTREAM_READER_LE + result>>= (index&0x07); + result&= 1; +#else + result<<= (index&0x07); + result>>= 8 - 1; +#endif + index++; + s->index= index; + + return result; +#else + return get_bits(s, 1); +#endif +} + +static inline unsigned int show_bits1(GetBitContext *s){ + return show_bits(s, 1); +} + +static inline void skip_bits1(GetBitContext *s){ + skip_bits(s, 1); +} + +/** + * reads 0-32 bits. + */ +static inline unsigned int get_bits_long(GetBitContext *s, int n){ + if(n<=MIN_CACHE_BITS) return get_bits(s, n); + else{ +#ifdef ALT_BITSTREAM_READER_LE + int ret= get_bits(s, 16); + return ret | (get_bits(s, n-16) << 16); +#else + int ret= get_bits(s, 16) << (n-16); + return ret | get_bits(s, n-16); +#endif + } +} + +/** + * reads 0-32 bits as a signed integer. + */ +static inline int get_sbits_long(GetBitContext *s, int n) { + return sign_extend(get_bits_long(s, n), n); +} + +/** + * shows 0-32 bits. + */ +static inline unsigned int show_bits_long(GetBitContext *s, int n){ + if(n<=MIN_CACHE_BITS) return show_bits(s, n); + else{ + GetBitContext gb= *s; + return get_bits_long(&gb, n); + } +} + +static inline int check_marker(GetBitContext *s, const char *msg) +{ + int bit= get_bits1(s); + if(!bit) + av_log(NULL, AV_LOG_INFO, "Marker bit missing %s\n", msg); + + return bit; +} + +/** + * init GetBitContext. + * @param buffer bitstream buffer, must be FF_INPUT_BUFFER_PADDING_SIZE bytes larger then the actual read bits + * because some optimized bitstream readers read 32 or 64 bit at once and could read over the end + * @param bit_size the size of the buffer in bits + * + * While GetBitContext stores the buffer size, for performance reasons you are + * responsible for checking for the buffer end yourself (take advantage of the padding)! + */ +static inline void init_get_bits(GetBitContext *s, + const uint8_t *buffer, int bit_size) +{ + int buffer_size= (bit_size+7)>>3; + if(buffer_size < 0 || bit_size < 0) { + buffer_size = bit_size = 0; + buffer = NULL; + } + + s->buffer= buffer; + s->size_in_bits= bit_size; + s->buffer_end= buffer + buffer_size; +#ifdef ALT_BITSTREAM_READER + s->index=0; +#elif defined LIBMPEG2_BITSTREAM_READER + s->buffer_ptr = (uint8_t*)((intptr_t)buffer&(~1)); + s->bit_count = 16 + 8*((intptr_t)buffer&1); + skip_bits_long(s, 0); +#elif defined A32_BITSTREAM_READER + s->buffer_ptr = (uint32_t*)((intptr_t)buffer&(~3)); + s->bit_count = 32 + 8*((intptr_t)buffer&3); + skip_bits_long(s, 0); +#endif +} + +static inline void align_get_bits(GetBitContext *s) +{ + int n= (-get_bits_count(s)) & 7; + if(n) skip_bits(s, n); +} + +#define init_vlc(vlc, nb_bits, nb_codes,\ + bits, bits_wrap, bits_size,\ + codes, codes_wrap, codes_size,\ + flags)\ + init_vlc_sparse(vlc, nb_bits, nb_codes,\ + bits, bits_wrap, bits_size,\ + codes, codes_wrap, codes_size,\ + NULL, 0, 0, flags) + +int init_vlc_sparse(VLC *vlc, int nb_bits, int nb_codes, + const void *bits, int bits_wrap, int bits_size, + const void *codes, int codes_wrap, int codes_size, + const void *symbols, int symbols_wrap, int symbols_size, + int flags); +#define INIT_VLC_LE 2 +#define INIT_VLC_USE_NEW_STATIC 4 +void free_vlc(VLC *vlc); + +#define INIT_VLC_STATIC(vlc, bits, a,b,c,d,e,f,g, static_size)\ +{\ + static VLC_TYPE table[static_size][2];\ + (vlc)->table= table;\ + (vlc)->table_allocated= static_size;\ + init_vlc(vlc, bits, a,b,c,d,e,f,g, INIT_VLC_USE_NEW_STATIC);\ +} + + +/** + * + * If the vlc code is invalid and max_depth=1, then no bits will be removed. + * If the vlc code is invalid and max_depth>1, then the number of bits removed + * is undefined. + */ +#define GET_VLC(code, name, gb, table, bits, max_depth)\ +{\ + int n, nb_bits;\ + unsigned int index;\ +\ + index= SHOW_UBITS(name, gb, bits);\ + code = table[index][0];\ + n = table[index][1];\ +\ + if(max_depth > 1 && n < 0){\ + LAST_SKIP_BITS(name, gb, bits)\ + UPDATE_CACHE(name, gb)\ +\ + nb_bits = -n;\ +\ + index= SHOW_UBITS(name, gb, nb_bits) + code;\ + code = table[index][0];\ + n = table[index][1];\ + if(max_depth > 2 && n < 0){\ + LAST_SKIP_BITS(name, gb, nb_bits)\ + UPDATE_CACHE(name, gb)\ +\ + nb_bits = -n;\ +\ + index= SHOW_UBITS(name, gb, nb_bits) + code;\ + code = table[index][0];\ + n = table[index][1];\ + }\ + }\ + SKIP_BITS(name, gb, n)\ +} + +#define GET_RL_VLC(level, run, name, gb, table, bits, max_depth, need_update)\ +{\ + int n, nb_bits;\ + unsigned int index;\ +\ + index= SHOW_UBITS(name, gb, bits);\ + level = table[index].level;\ + n = table[index].len;\ +\ + if(max_depth > 1 && n < 0){\ + SKIP_BITS(name, gb, bits)\ + if(need_update){\ + UPDATE_CACHE(name, gb)\ + }\ +\ + nb_bits = -n;\ +\ + index= SHOW_UBITS(name, gb, nb_bits) + level;\ + level = table[index].level;\ + n = table[index].len;\ + }\ + run= table[index].run;\ + SKIP_BITS(name, gb, n)\ +} + + +/** + * parses a vlc code, faster then get_vlc() + * @param bits is the number of bits which will be read at once, must be + * identical to nb_bits in init_vlc() + * @param max_depth is the number of times bits bits must be read to completely + * read the longest vlc code + * = (max_vlc_length + bits - 1) / bits + */ +static av_always_inline int get_vlc2(GetBitContext *s, VLC_TYPE (*table)[2], + int bits, int max_depth) +{ + int code; + + OPEN_READER(re, s) + UPDATE_CACHE(re, s) + + GET_VLC(code, re, s, table, bits, max_depth) + + CLOSE_READER(re, s) + return code; +} + +//#define TRACE + +#ifdef TRACE +static inline void print_bin(int bits, int n){ + int i; + + for(i=n-1; i>=0; i--){ + av_log(NULL, AV_LOG_DEBUG, "%d", (bits>>i)&1); + } + for(i=n; i<24; i++) + av_log(NULL, AV_LOG_DEBUG, " "); +} + +static inline int get_bits_trace(GetBitContext *s, int n, char *file, const char *func, int line){ + int r= get_bits(s, n); + + print_bin(r, n); + av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d bit @%5d in %s %s:%d\n", r, n, r, get_bits_count(s)-n, file, func, line); + return r; +} +static inline int get_vlc_trace(GetBitContext *s, VLC_TYPE (*table)[2], int bits, int max_depth, char *file, const char *func, int line){ + int show= show_bits(s, 24); + int pos= get_bits_count(s); + int r= get_vlc2(s, table, bits, max_depth); + int len= get_bits_count(s) - pos; + int bits2= show>>(24-len); + + print_bin(bits2, len); + + av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d vlc @%5d in %s %s:%d\n", bits2, len, r, pos, file, func, line); + return r; +} +static inline int get_xbits_trace(GetBitContext *s, int n, char *file, const char *func, int line){ + int show= show_bits(s, n); + int r= get_xbits(s, n); + + print_bin(show, n); + av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d xbt @%5d in %s %s:%d\n", show, n, r, get_bits_count(s)-n, file, func, line); + return r; +} + +#define get_bits(s, n) get_bits_trace(s, n, __FILE__, __PRETTY_FUNCTION__, __LINE__) +#define get_bits1(s) get_bits_trace(s, 1, __FILE__, __PRETTY_FUNCTION__, __LINE__) +#define get_xbits(s, n) get_xbits_trace(s, n, __FILE__, __PRETTY_FUNCTION__, __LINE__) +#define get_vlc(s, vlc) get_vlc_trace(s, (vlc)->table, (vlc)->bits, 3, __FILE__, __PRETTY_FUNCTION__, __LINE__) +#define get_vlc2(s, tab, bits, max) get_vlc_trace(s, tab, bits, max, __FILE__, __PRETTY_FUNCTION__, __LINE__) + +#define tprintf(p, ...) av_log(p, AV_LOG_DEBUG, __VA_ARGS__) + +#else //TRACE +#define tprintf(p, ...) {} +#endif + +static inline int decode012(GetBitContext *gb){ + int n; + n = get_bits1(gb); + if (n == 0) + return 0; + else + return get_bits1(gb) + 1; +} + +static inline int decode210(GetBitContext *gb){ + if (get_bits1(gb)) + return 0; + else + return 2 - get_bits1(gb); +} + +static inline int get_bits_left(GetBitContext *gb) +{ + return gb->size_in_bits - get_bits_count(gb); +} + +#endif /* AVCODEC_GET_BITS_H */ |